> So I think the "let's fix the vdso case for sysenter" + "let's remove> the 32-bit syscall vdso" is the right solution. If somebody has> hardcoded syscall instructions, or generates them dynamically with> some JIT, that's their problem. We'll continue to support it as well> as we ever have (read: "almost nobody will ever notice").

Umm... Maybe, but I really wonder if it would be better to do this: * check if %ecx is the right one for vdso32 entry. If it isn't,act as we act now (and possibly warn). If it is, increment it by 4. * slap 0x90, 0x90, 0xcd, 0x80 right after that syscall insn -i.e. nop/nop/int 0x80. Followed by what we currently do there.

Those who do syscall insn in 32bit mode outside of vdso will getwhat they currently get. __kernel_vsyscall() will keep working and dothat without restart problems. And the price is comparison + branch nottaken + addition for that path...